| 主权项 |
1. A device for receiving and processing signals reflected from objects in the ground comprising
a rod to be inserted into the ground, a radar information generating unit including an antenna provided in the rod for transmitting radar signals into the ground, at least one signal receiving unit provided in the rod for receiving radar signals reflected from an object in the ground, and a signal processing unit connected to the at least one signal receiving unit and containing as units for main detection i) a band-pass filter that blocks frequencies outside the interval 0.3-10 Hz, ii) a differential detector that compares the amplitudes of the signals that have passed the band-pass filter to create a derivative of the received signals, of which the absolute value is created, and iii) a comparator and decision processor unit that compares the absolute value of the derivative with a threshold value that corresponds to the background noise in the collapsed ground and decides whether a reflected signal has been Doppler shifted in a way that is likely to be by the breathing movement of a buried person, characterized in that the rod in its length direction is divided into multiple sections, each section of the rod having thereon the at least one signal receiving unit connected to the signal processing unit, the sections corresponding to different length segments of the rod and providing indication of the ground depth where a moving object has been detected, and characterized in that each section is radially divided into sectors disposed peripherally around the rod, each sector carrying the at least one signal receiving unit connected to the signal processing unit, whereby signals received by a specific receiving unit are processed to determine whether a reflected radar signal has been Doppler shifted and thereby determine whether an object in the ground is moving, each sector providing information about angular positioning of the object relative the rod where the Doppler shift was detected. |
